Mechanisms

This topic covers the relationship between force, area and pressure; calculating force, area and pressure using the equation; calculating values in a hydraulic pressure system; and describing use of hydraulics on racing boats.

The resources in BT STEM Crew can be used either in sequence or flexibly as an introduction to a topic, or for a quick activity.

Introduce the topic of mechanisms with a short starter film, discussing how levers, pulleys, gears and hydralics are used to steer the boat. Test students' knowledge with an engaging interactive. Our differentiated worksheets reinforce learning objectives for this topic.

Film

How do wings, hulls and grinders work to operate and control the boat? Find out about the different mechanisms used to get the best performance.

Interactive quiz

See how much your students know about force, area and pressure to understand how the Land Rover BAR team analyse the boat hydraulics to maximise their performance.

Practical Investigation: Presentation

Practical Investigation: Lab Sheet

Practical Investigation: Teacher Guide

Teacher's notes

Starter

To introduce the topic you could have a pair of tools to show students, such as embroidery scissors and kitchen scissors, wire cutters and bolt cutters, or large and small spanners. Ask them what the advantages and disadvantages of each are, and elicit the idea that the longer handles make it possible to exert a larger force at the cutting point/nut.

Suggested activity

Students investigate the force needed to lift a given mass with a single pulley, two pulleys, etc. Also measure how far the force has to move to lift the mass by a given amount, and work out that force x distance is always the same (with allowances for friction). Suggest similar hydraulic activity with syringes and tubes.

Plenary

Find images on the internet of an open sailing dinghy and ask them to identify similarities and differences between this and the racing boat in terms of simple machines. They should point out that both use pulleys to control the sail, both have tillers, but the dinghy does not have winches or hydraulics. Ask them to suggest why this is (less force needed as a much smaller sail area) and if this is so, why pulleys etc. are still needed (crew not usually as strong!)

Further ideas/ STEM Club ideas

Find out about capstans used on old ships (before steam power) to raise anchors etc. – how are they similar and different to the winches on the Land Rover BAR boats? (much bigger, worked by longer bars and many men, no gears)

Scientific principles: The importance of scientific principles in common products such as levers, and mechanisms on bicycles ; understanding how modern scientific principles and new materials have influenced the design of products.

Wales

KS3 Science

Understand the forces in devices and their relationship to work done and power

KS3 Design & Technology

Learn about the properties and characteristics of mechanical components and apply this knowledge and understanding when designing and making products

GCSE Physics

WJEC

Demonstrate and apply knowledge and understanding of the concept of pressure qualitatively and select and use the relationship: force = pressure / area